Heart Attack

What is a heart attack (myocardial infarction)?

A heart attack, or myocardial infarction, occurs when one or more regions of the heart muscle experience a severe or prolonged lack of oxygen caused by blocked blood flow to the heart muscle.

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The blockage is often a result of atherosclerosis—a buildup of plaque composed of fat deposits, cholesterol, and other substances. When a plaque ruptures, a blood clot quickly forms. The blood clot is the actual cause of the heart attack.

If the blood and oxygen supply is cut off, muscle cells of the heart begin to suffer damage and start to die. Irreversible damage begins within 30 minutes of blockage. The result is dysfunction of the heart muscle in the area affected by the lack of oxygen or cell death.

What are the risk factors for heart attack?

There are two types of risk factors for heart attack, including the following:

Inherited (or genetic)

Acquired

Inherited or genetic risk factors are risk factors you are born with that cannot be changed, but can be improved with medical management and lifestyle changes.

Acquired risk factors are caused by activities that we choose to include in our lives that can be managed through lifestyle changes and clinical care.

Inherited (genetic) factors: Who is most at risk?

People with inherited hypertension (high blood pressure)

People with inherited low levels of HDL (high-density lipoproteins), high levels of LDL (low-density lipoprotein) blood cholesterol or high levels of triglycerides

People with a family history of heart disease (especially with onset before age 55)

Aging men and women

People with type 1 diabetes

Women, after the onset of menopause (generally, men are at risk at an earlier age than women, but after the onset of menopause, women are equally at risk)

Acquired risk factors: Who is most at risk?

People with acquired hypertension (high blood pressure)

People with acquired low levels of HDL (high-density lipoproteins), high levels of LDL (low-density lipoprotein) blood cholesterol, or high levels of triglycerides

Cigarette smokers

People who are under a lot of stress

People who drink too much alcohol

People who lead a sedentary lifestyle

People overweight by 30 percent or more

People who eat a diet high in saturated fat

People with type 2 diabetes

A heart attack can happen to anyone—it is only when we take the time to learn which of the risk factors apply to us, specifically, can we then take steps to eliminate or reduce them.

Managing heart attack risk factors

Managing your risks for a heart attack begins with:

Examining which of the risk factors apply to you, and then taking steps to eliminate or reduce them.

Becoming aware of conditions like hypertension or abnormal cholesterol levels, which may be "silent killers."

Modifying risk factors that are acquired (not inherited) through lifestyle changes. Consult your doctor as the first step in starting right away to make these changes.

Consulting your health care provider soon to determine if you have risk factors that are genetic or inherited and cannot be changed, but can be managed medically and through lifestyle changes.

What are the warning signs of a heart attack?

The following are the most common symptoms of a heart attack. However, each individual may experience symptoms differently. Symptoms may include:

Severe pressure, fullness, squeezing, pain and/or discomfort in the center of the chest that lasts for more than a few minutes

Pain or discomfort that spreads to the shoulders, neck, arms, or jaw

Chest pain that increases in intensity

Chest pain that is not relieved by rest or by taking nitroglycerin

Chest pain that occurs with any/all of the following (additional) symptoms:

Sweating, cool, clammy skin, and/or paleness

Shortness of breath

Nausea or vomiting

Dizziness or fainting

Unexplained weakness or fatigue

Rapid or irregular pulse

Although chest pain is the key warning sign of a heart attack, it may be confused with indigestion, pleurisy, pneumonia, or other disorders.

The symptoms of a heart attack may resemble other medical conditions or problems. Always consult your health care provider for a diagnosis.

Responding to heart attack warning signs

If you or someone you know exhibits any of the above warning signs, act immediately. Call 911, or your local emergency number.

Treatment for a heart attack

The goal of treatment for a heart attack is to relieve pain, preserve the heart muscle function, and prevent death.

Treatment in the emergency department may include:

Intravenous therapy such as nitroglycerin and morphine.

Continuous monitoring of the heart and vital signs.

Oxygen therapy improves oxygenation to the damaged heart muscle.

Pain medication decreases pain, and, in turn, decreases the workload of the heart, thus, the oxygen demand of the heart decreases.

Fibrinolytic therapy is the intravenous infusion of a medication which dissolves the blood clot, thus, restoring blood flow.

Antithrombin/antiplatelet therapy is used to prevent further blood clotting.

Antihyperlipidemics are medications used to lower lipids (fats) in the blood, particularly Low Density Lipid (LDL) cholesterol. Statins are a group of antihyperlipidemic medications, and include simvastatin (Zocor), atorvastatin (Lipitor), and pravastatin (Pravachol), among others. Bile acid sequestrants—colesevelam, cholestyramine, and colestipol—and nicotinic acid (niacin) are two other types of medications that may be used to reduce cholesterol levels.

Additional procedures to restore coronary blood flow may be used. Those procedures include:

Coronary angioplasty. With this procedure, a balloon is used to create a bigger opening in the vessel to increase blood flow. This is often followed by the insertion of a stent into the coronary artery to help keep the vessel open. Although angioplasty is performed in other blood vessels elsewhere in the body, percutaneous coronary intervention (PCI) refers to angioplasty in the coronary arteries to permit more blood flow into the heart. PCI is also called percutaneous transluminal coronary angioplasty (PTCA). There are several types of PTCA procedures, including:

Balloon angioplasty. A small balloon is inflated inside the blocked artery to open the blocked area.

Coronary artery stent. A tiny coil is expanded inside the blocked artery to open the blocked area and is left in place to keep the artery open.

Atherectomy. The blocked area inside the artery is cut away by a tiny device on the end of a catheter.

Laser angioplasty. A laser used to "vaporize" the blockage in the artery.

Coronary artery bypass. Most commonly referred to as simply "bypass surgery" or CABG (pronounced "cabbage"), this surgery is often performed in people who have angina (chest pain) and coronary artery disease (where plaque has built up in the arteries). During the surgery, a bypass is created by grafting a piece of a vein above and below the blocked area of a coronary artery, enabling blood to flow around the obstruction. Veins are usually taken from the leg, but arteries from the chest or arm may also be used to create a bypass graft.

Treatment Programs

Massachusetts General Hospital understands that a variety of factors influence patients' health care decisions. That's just one reason why we're dedicated to ensuring patients understand their diagnosis and treatment options. Because a single option might not serve all patients, we offer a wide range of coordinated treatments and related services across the hospital. Patients should consult with their primary care doctor or other qualified health care provider for medical advice and diagnosis information.

Weight CenterThe Massachusetts General Hospital Weight Center is a fully integrated center within the Digestive Healthcare Center that supports the spectrum of needs for people of all ages seeking help with obesity and weight loss.

Cardio-Oncology Program The Massachusetts General Hospital Cardio-Oncology Program provides care at the intersection of heart and vascular disease, and cancer. The program focuses on improving the health of cancer patients and cancer survivors by providing comprehensive cardiac and vascular care.

Heart Failure and Cardiac Transplant ProgramThe Heart Failure and Cardiac Transplant Program at the Massachusetts General Hospital Corrigan Minehan Heart Center evaluates and manages a range of heart disease conditions that result in heart failure.

Corrigan Women's Heart Health ProgramThe Elizabeth Anne and Karen Barlow Corrigan Women's Heart Health Program at the Massachusetts General Hospital Corrigan Minehan Heart Center cares for women of all ages through prevention and early detection of heart disease.

Midlife Women's Health CenterThe Massachusetts General Hospital Midlife Women’s Health Center brings together experts from more than 15 specialties to improve, promote and advance health care for women at menopause and beyond through research, collaboration and education.

Cardiac Wellness Program: Reduce Cardiac RiskHeart disease is the number one cause of death in the U.S. for both men and women. Although genetics plays a role in the development of heart disease, lifestyle choices have been proven to significantly influence the health of your heart. The more risk factors you have, the greater your chance of having a heart attack or stroke. This program is held at MGH West in Waltham, MA.

Bariatric and Metabolic Surgery ProgramThe Bariatric and Metabolic Surgery Program at Massachusetts General Hospital offers a full spectrum of safe and effective surgical procedures for obesity, weight disorders and metabolic disease.

MGH Hotline 2.18.11 Just in time for Valentine’s Day, the MGH Heart Center and Corrigan Women’s Heart Health Program brought attention to hearts everywhere by celebrating “Go Red for Women” month with a series of events and activities to raise awareness of heart disease in women.

MGH Hotline 4.1.11 From the time a person first experiences symptoms of a heart attack, such as shortness of breath or chest discomfort, to the time he or she undergoes cardiac catheterization -- a procedure used to diagnose and treat a blocked coronary artery -- every second is of utmost importance.

Just in time for American Heart Month, a new survey says Americans are confused about what it means to eat a heart-healthy diet. Armed with tips to tackle any confusion, MGH dietician Deborah Krivitsky, MS, RD, LDN, of the Cardiovascular Disease Prevention Center in the Institute for Heart, Vascular and Stroke Care, shares some diet tips that can help lower the risk for heart disease.

Malissa Wood, MD, Co-Director of the Corrigan Women's Heart Health Program at the Massachusetts General Hospital Heart Center describes the heart attack symptoms that are unique to women, and why treatment of heart disease should be gender-specific.

Sekar Kathiresan, MD, Director of Preventive Cardiology at the Massachusetts General Hospital Heart Center says counteracting your genetic risk is within your control. Learn more about coronary artery disease, who is most at risk and about Mass General's Heart Attack Prevention Program, focused on people with a family history of the disease.

Aaron Baggish, MD, Associate Director for the Cardiovascular Performance Program at the Massachusetts General Hospital Heart Center explains how heart problems are diagnosed in highly active people and how Mass General specialists help them exercise safely to reduce the risk of heart attack.